Obstructive sleep apnea and obstructive breathing (snoring) is mainly caused by the collapse of the airway at the back of the throat. This occurs when the tongue falls to the back of the throat and blocks the airway. In snoring, the air forcibly passes, causing loud vibrations. In obstructive sleep apnea (OSA), the airway is completely blocked by the tongue and the patient cannot breathe at all. This condition exists for at least 10 seconds but can last up to 70-80 seconds. As the oxygen level in the blood begins to fall, the brain becomes alerted and eventually wakes up the patient--usually with a loud gasp, thrashing, and extreme vibrating noises. As soon as the patient's breathing returns to normal, the situation reoccurs, over and over again. This can occur 400-500 times a night, in severe cases.